1. Field of the Invention
The present invention is related to a novel electric meter with a single key, and especially to a hooking-type fully automatic electric meter convenient for measuring in a hooking and hanging mode, a user only needs to turn on the electric power of the electric meter without performing any other procedures, he can get an accurate reading of the volume of electricity on the display screen. The electric meter has the function of fully automatic detecting and choosing a measuring mode among the electric current, voltage and resistance measuring modes.
2. Description of the Prior Art
Electric meters available nowadays can be divided generally into two kinds, those are the LCD (liquid crystal display) and the mechanical types. The meters normally seen, in addition to evident indication of the difference on the meters, are provided with operating rotation knobs for multi-stage function switching, and are provided near the difference indication with function indication to allow a user to manually select and move according to the detecting item he desire to switch to a related measuring electric character and to the position within the scope of value to be detected. Such a measuring mode practically still needs that a user has substantial ability of judging in electric measuring, an initial learner or one who is not familiar with this will induce a wrong measuring value by inaccurate selection of position, and even may damage the electric meter seriously when errors are resulted by wrong selection in using for high voltage or large current, and this may be dangerous to the safety of the user himself.
Although there has been automatic electric meters in the markets that can solve the defects stated above by unfamiliarity with position adjustment and control, they only have the basic functions of three kinds of automatic measuring including AC voltage, DC voltage and resistance measuring, and are unable to make an automatic measuring in a hooking and hanging mode, for an AC electric current. Thereby, the range of measuring of such meters is largely limited.
In view of the defects resided in the conventional single-key electric meters in application, the inventor of the present invention studied deeply and developed the novel electric meter of the present invention.
The main object of the present invention is to provide a fully automatic electric meter for fully automatic detecting and switching for choosing to do four kinds of measuring including AC voltage, DC voltage, AC electric current and resistance measurement in a mode of hooking and hanging on any electric line by a user at his own will.
The secondary object of the present invention is to provide a safe and accurate fully automatic hooking-mode electric meter with a sequential of priority of measuring and a judging function on related measuring electric characters. A user needs only to turn on the electric power of the electric meter without performing any otherr procedures, and can get an accurate reading of the volume of electricity on the display screen.
Another object of the present invention is to provide a fully automatic hooking-mode electric meter that is operated with a single key and has a stationary temporary xe2x80x9cHOLDxe2x80x9d mode in favor of convenient measuring electric values which are easily readable for discrimination.
To achieve the above objects, the fully automatic hooking-mode electric meter of the present invention is mainly comprised of: a main body of the electric meter provided thereon with a display and a single operating key (hold key power switch), the main body is provided at suitable positions thereon with insertion lines having detecting probes and is provided on the top thereof with an electric current sensing clamp receiving therein a current carrying conductor; a switching mechanism with an auto selection function for judging and selection through the main body of the electric meter under inputting from the outside during the xe2x80x9conxe2x80x9d state of the electric meter, it can provide four kinds of measuring modes including DC voltage, AC voltage, electric resistance and AC electric current measuring; and a detecting mechanism with priority, with which, the signal inputting through the probes takes priority of the signal inputting through the electric current sensing clamp, the electric meter thereby can automatically intelligently switch by single key manipulating to save actions and time for operating the electric meter; and the electric meter can be hung by hooking on any electric line in favor of convenient observing the measuring electric values, thereby, convenience and efficiency in operating can be increased, and error of adjustment in operating by a user can be avoided, thus damage to the main body of the electric meter and to the safety of the user himself can be avoided too. This can significantly raise the industrial safety in measuring large volume of electric current.
The present invention will be apparent in its particular operation and functions after reading the detailed description of the preferred embodiments thereof in reference to the accompanying drawings.